Driver circuitry and systems for high current laser diode arrays

Abstract

Apparatuses, methods, and systems are disclosed to drive pumping laser diode arrays. In implementations, an integrated system can be constructed to in a compact, efficient and cost-effective manner and to meet the needs of driving laser diode arrays in various diode pumped solid state laser applications. The disclosed implementations include individual laser diode drivers or pulsers, methods of communicating with laser diode drivers, and methods of controlling the pulse shape of each laser diode driver.

What is claimed is: 
     
       1. An apparatus for operating a plurality of laser diode arrays coupled to a laser pulser unit, comprising:
 a controller to control a current wave shape or a current amplitude driven into each laser diode in each of the laser diode arrays, wherein the controller is configured to adjust the current wave shape or the current amplitude for each laser in the laser diode array according to a command; 
 a plurality of optical receivers coupled to the controller, the plurality of optical receivers configured to receive the command, wherein the command is a broadcast command to control the current wave shape or the current amplitude of a plurality of laser diodes together, or an addressed command to control the current wave shape or the current amplitude of one of the plurality of laser diodes; 
 a plurality of driver circuits positioned inside the laser pulser unit and coupled to the plurality of optical receivers to receive the command from the controller, the plurality of driver circuits further coupled to the plurality of the laser diode arrays by a plurality of cables having a predetermined inductance characteristic, wherein an adjustment to the current wave shape or current amplitude includes a change in the current pulse shape or current pulse amplitude to compensate for the predetermined inductance characteristic in each of the plurality of cables; and 
 a single energy discharge unit coupled to a fault detection system, the energy discharge unit comprising a plurality of resistors and configured to discharge energy stored in all driver circuits of the laser pulser unit through the set of resistors in response to receiving a signal indicative of an anomalous laser diode output current or output power from the fault detection system. 
 
     
     
       2. The apparatus of  claim 1 , wherein the controller is configured to at least:
 receive feedback information relating to a measured current into an associated laser diode and a measured optical output from the associated laser diode, and 
 upon detecting an anomaly in the measured current or a measured optical output, adjust the current amplitude or wave shape via a command; and 
 send the command to control the current amplitude or wave shape into the associated laser diode. 
 
     
     
       3. The apparatus of  claim 2 , wherein the wave shape is adjusted in at least one of:
 a rise time of a pulse; 
 a fall time of the pulse; 
 an amplitude of the pulse; or 
 a width of the pulse. 
 
     
     
       4. The apparatus of  claim 2 , wherein the controller is configured to at least:
 monitor data from one or more sensors included in the apparatus. 
 
     
     
       5. The apparatus of  claim 4 , wherein the monitored data from the one or more sensors includes at least one of:
 a diode coolant temperature; 
 a diode flow switch status; 
 a diode humidity; 
 a pulser coolant flow rate; 
 a pulser outlet temperature; or 
 a voltage provided by a direct current power supply. 
 
     
     
       6. The apparatus of  claim 1 , further comprising:
 one or more processors and memory, wherein the one or more processors is further configured to communicate via an Ethernet interface. 
 
     
     
       7. The apparatus of  claim 6 , wherein the one or more processors includes an integrated field programmable gate array. 
     
     
       8. A method for controlling a laser diode array, comprising:
 controlling, by a controller, a current wave shape or a current amplitude driven into each laser diode in the laser diode array, wherein the controller adjusts the current wave shape or the current amplitude according to a command, wherein an adjustment to the current wave shape or current amplitude includes a change in the current pulse shape or current pulse amplitude to compensate for a predetermined inductance characteristic in each of a plurality of cables connecting a plurality of driver circuits to laser diodes in the laser diode array; 
 receiving, by a plurality of optical receivers coupled to the controller, the command, wherein the command is a broadcast command to control the current wave shape or the current amplitude of a plurality of laser diodes together, or an addressed command to control the current wave shape or the current amplitude of one of the plurality of laser diodes; 
 receiving a signal indicative of an anomalous laser diode output current or output power from a fault detection system; and 
 using a single energy discharge unit comprising a plurality of resistors to discharge energy stored in all driver circuits through the set of resistors in response to receiving the signal indicative of an anomalous laser diode output current or output power. 
 
     
     
       9. The method of  claim 8 , wherein the controller is configured to at least:
 receive feedback information relating to a measured current into the associated laser diode and a measured optical output from the associated laser diode; 
 upon detecting an anomaly in the measured current or a measured optical output, adjust the current amplitude or wave shape via a command; and 
 send the command to control the current amplitude or wave shape into an associated laser diode. 
 
     
     
       10. The method of  claim 9 , wherein the wave shape is adjusted in at least one of:
 a rise time of a pulse; 
 a fall time of the pulse; 
 an amplitude of the pulse; or 
 a width of the pulse.